1. Field of the Invention
The present invention relates to an electric facility, and more particularly to an electric facility having a device for anti-electromagnetic interference purposes.
2. Description of the Prior Art
Typical electric facilities comprise a number of electric parts or elements disposed on a circuit board, and one or more high frequency cables attached thereto or disposed close thereto. An electromagnetic action or field may be generated by or in the high frequency cables, and may thus generate noises or miscellaneous or unwanted signals or the like in the electric parts or elements; i.e., the electric parts or elements may be interfered by the electromagnetic action or the electromagnetic field generated by or in the high frequency cables. This is so-called the anti-electromagnetic interference (abbreviated as EMI hereinafter). Accordingly, how to eliminate or decrease the EMI against the electric facility will become more and more important.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional electric facilities.
The primary objective of the present invention is to provide an electric facility including a device for anti-electromagnetic interference purposes and for preventing noises or miscellaneous or unwanted signals or the like from being generated in the electric parts or elements.
In accordance with one aspect of the invention, there is provided an electric facility comprising a primary circuit board, a cover secured on the primary circuit board, the cover including at least one orifice formed therein, a circuit unit disposed on the primary circuit board and received in the cover, and including at least one socket engaged through the orifice of the cover, and a cable including a first end having a plug provided thereon, the plug including a tube extended therefrom for engaging into the socket and for coupling to the circuit unit.
The circuit unit includes a secondary circuit board having a first conductor engaged in the socket of the circuit unit. The plug includes a second conductor engaged in the tube for engaging with the first conductor of the socket. The conductors may be suitably shielded or protected within the socket and the tube and may thus be further prevented from being interfered by the outer electromagnetic field or environment or may be prevented from the EMI.
The circuit unit includes a housing for receiving the secondary circuit board and for shielding the secondary circuit board. The housing is preferably a metal housing. The secondary circuit board may be suitably shielded by the housing which may prevent the secondary circuit board from being interfered by the outer electromagnetic field or environment or may prevent the EMI against the secondary circuit board.
The cover includes at least one ear extended therefrom and provided around the orifice of the cover for engaging with the socket and for grounding the socket.
A device is further provided for positioning the circuit unit on the primary circuit board and includes a seat disposed on the primary circuit board for supporting the circuit unit.
The circuit unit includes at least one notch formed therein, the seat includes at least one projection extended therefrom and engaged into the notch of the circuit for securing the circuit unit on the primary circuit board.
The positioning device includes a row of pins disposed and extended on the primary circuit board for engaging with and for positioning the circuit unit relative to the primary circuit board.
The primary circuit board includes at least one groove formed therein, the cover includes at least one hook extended for engaging into the groove of the primary circuit board and for securing the cover on the primary circuit board, the cover includes at least one reinforcing rib provided thereon for reinforcing purposes.
The primary circuit board includes a coupler disposed thereon, the cover includes a plurality of flaps extended therefrom for engaging onto the coupler of the primary circuit board and for positioning the cover on the primary circuit board.